Energy Harvesting Chip Demonstrated

PORTLAND, Ore. — Energy harvesting chips can power sensors in hard-to-reach locations, providing power indefinitely to sensor nodes without maintenance, according to the collaborators Imec (formerly Interuniversity Microelectronics Centre) of Leuven, Belgium, and Omron Corp. in Kyoto, Japan. Their prototype weighs just 15.4 grams and harvests vibrations on equipment to provide DC power to sensors in the microwatt range. It is being shown for the first time at Techno-Frontier 2014 in Tokyo, July 23 to 25.

Omron's part was to build the "electret" energy harvester portion of the two-part device, married to a power management chip from Imec, all housed in the same package. The collaborators hope to shrink future versions of the energy harvesting chip from 5x6 down to 2x2 centimeters. The companies claim the device can be tuned to harvest vibrational energy from industry equipment and transmit sensor data thereby putting industrial equipment on the Internet of Things (IoT).

Imec and Omron will show off their prototype energy harvester board at Techno-Frontier 2014. The board weighs 15.4 grams and harvests vibrations on equipment to provide DC power to sensors in the microwatt range. (Source: Imec)

Current-day energy harvesters are too large and heavy for many remote sensor applications, according to René Elfrink, senior researcher for sensors and energy harvesters at Imec's Holst Centre. Imec's power management chip allows the vibrational energy from Omron's electret harvester to accumulate and produce a constant supply voltage between 1.5 and 5 volts, according to Daido Uchida, general manager of the Technology Produce and Startup division of Omron.

Omron has not announced a date for the commercial product version of the energy harvester and is currently field testing the unit with key customers.

We may see an arms race between the energy harvesters and the energy wasters. All the energy that gets harvested (and it is a small fraction of the total ambient wasted energy) is being produced by something. If the energy producer better balances their motor, they reduce their wasted mechanical energy (while cutting off the harvester). If an electrical system is broadcasting unused energy, it is being inefficient. I'll be interested to see how systems start reducing radiated energy or recovering the energy to improve efficiency rather than just leaving it there for a few random devices to harvest.

In the most extreme cases, I wonder if the energy harvesters will start putting a measurable load on the energy producer and forcing them to increase their energy consumption to cover their work as well as the parasitic loads.

The current Imec/Omron prototype generates 70 microAmps with at 1 volt would be 70 microWatts--10 for the sensor and 60 for the comm--plus they claim to be working on upping the output. However, its not a product yet00-only time will tell.

Well, to read at 10 uA, 1V, there is already 10 uW involved, and obviously we need many times more than this power for processing, so I do think energy harvesting is currently insufficient to meet energy needs. And don't think energy harvesting doesn't have its environmental consequences. Energy that is harvested comes from somewhere, and we expect that energy will not be replenished at the source?

Most of the traffic IOT (IOT that is outside relaying traffic, both human and vehicular, data to clouds) will benefit from this kind of an energy harvesting technology because IOT power generation is a hotly debated topic, and this seems to cool down the waves of people saying IOT cannot be funded because the energy costs are too high.

Imec/Omron seem to think there are applications in that range. Here is what they said when I sent them your comment: "The energy harvester can generate up to 70 microwatt of DC power at the required (user-defined) voltage. It starts generating power from very low vibration conditions ( < 0.1 g). To operate a battery-less wireless sensor node 5 to 10 microwatts is sufficient, so even at low vibrations this power supply offers a solution for low-power wireless sensors."